Many Africans earn or hold USDC but must off-ramp to use it, losing time and money. Our product currently lets users instantly redeem USDC for airtime, no exchanges, no intermediaries. It’s a faster, cheaper, and safer way to turn crypto into everyday utility.

1. Cross-Chain Wallet Integration Complexity
Problem: Users might connect wallets on different networks (Ethereum, Polygon, etc.) but the app requires Base Mainnet for USDC transactions.

Solution: Implemented automatic network detection and switching:

2. ERC-20 Permit Signature Generation
Problem: Traditional ERC-20 approvals require two transactions (approve + transfer), creating poor UX and higher gas costs.

Solution: Implemented EIP-2612 permit signatures for gasless approvals:

• Generated off-chain permit signatures
• Combined approval and transfer in single transaction
• Reduced user friction from 2 transactions to 1
  (doens't work fully)

3. Error Handling and User-Friendly Messages
Problem: Blockchain errors are technical and confusing for end users.

Solution: Implemented error transformation layer:

https://github.com/FredMunene/topizzy

https://topizzy.vercel.app

Topizzy makes stablecoins truly useful in everyday life by enabling users to buy airtime instantly using USDC on Base. While most crypto apps focus on trading or DeFi, Topizzy connects digital assets to real-world utility, starting with something nearly every mobile user in Africa needs daily: airtime.

Our alpha build demonstrates this by providing a fully on-chain experience powered by Base.

Our target customers are crypto users and onchain builders in East Africa who hold USDC or other stablecoins and are looking for real-world ways to spend them. This includes freelancers, blockchain community members, and DeFi users who already interact with Web3 wallets like Coinbase Wallet or MetaMask.

We validated this audience through community conversations and testing within local crypto groups and developer communities in Kenya, Tanzania, and Uganda. Early testers on Farcaster and Baseapp showed strong interest in using USDC for everyday needs like airtime, confirming demand for practical, low-cost onchain utilities.

Competitor
Bitrefill – https://www.bitrefill.com/ug/en/
They allow users in Uganda to buy phone top-ups, gift cards, eSIMs and other digital goods using a variety of cryptocurrencies including USDC.
Their model is global-oriented, offering a broad catalogue of goods (not only airtime) and many crypto payment options.
How Topizzy Is Different / Better

• Business model clarity: Topizzy charges a flat fee of $0.05 per transaction and offers automatic refunds for failed transactions; this transparent fee structure and refund policy help build trust among users.

• Regional market fit: Topizzy explicitly targets East African mobile users (e.g., Kenya, Tanzania, Uganda) and leverages high mobile penetration and crypto adoption in those regions. This localization allows deeper relevance than a global-catalog model.

• Web3 native flow: Integration with crypto wallets, smart contracts and the Base network means users remain in their wallet environment; fewer bridges, fewer steps, nearly native crypto spending. Bitrefill’s flow may involve off-ramps, email codes, and multiple tokens, which can complicate the user journey.